Textile machine



J. M. PESTARINI TEXTILE MACHINE Filed March 26, 1951 FIGZ FIGA

NV ENTO R Jose 0Z2 .if/ eszarml 5 24/41: TTORNEY United States Patent TEXTILE MACHENE Joseph Maximus Iestarini, Staten Island, N. Y. Application March 26, 1951, Serial No. 217,515 4 Claims. (Cl. 318230) This invention relates to electromagnetic devices which are particularly adapted for use as textile weaving machines.

In weaving machinery, various devices have been proposed for propelling the shuttles between the warp threads, including electromagnetic means. However, known shuttle propelling means have a number of dis advantages, particularly in respect to maintaining the shuttle within a predetermined path and where a plurality of shuttles are used, keeping a predetermined spacing between successive shuttles.

Accordingly, an object of this invention is to provide in a loom, improved electromagnetic means for propelling one or more shuttles in free flight at a uniform rate of movement and in an undeviating path, whereby the shuttles do not contact the warp threads during the concurrent movement of the shuttles and warp threads.

A further object of this invention is to provide in a device of the character described, electromagnetic means defining an extended air gap and including a polyphase winding, together with one or more freely movable shuttles or the like having electrical conductors mounted thereon and adapted to move in the air gap, and a source of special polyphase currents for supply to the winding whereby to set up a movable magnetic flux in interlinked relation to the conductors on the shuttles and to cause determined movement in a predetermined path in the air gap.

Another object of this invention is to provide in a device of the character described, a pair of opposed polyphase windings located on opposite sides of an air gap and energized from a source of special polyphase currents, together with means for regulating the input voltage to the respective windings whereby to regulate the path of freely moving shuttles in the air gap and means for halting the movement of the shuttles.

Other objects of this invention will in part be obvious and in part hereinafter pointed out.

The invention accordingly consists in the combination of elements, arrangement of parts and circuit connections, which will be exemplified in the constructions hereinafter described, and of which the scope of invention will be indicated in the claims following.

In the accompanying drawing, in which is shown illustrative embodiments of the invention:

Fig. l is a schematic presentation of one form of the invention;

Fig. 2 is a vertical sectional view through a portion thereof;

Fig. 3 is a perspective view of a shuttle;

Fig. 4 is a schematic presentation of another form of the invention.

Referring in detail to the drawing and particularly to Fig. 1, 1i) designates a portion of a loom or the like, embodying the invention. The same comprises a pair of annular, concentric members 11, 12 which are spaced to provide an annular air gap 13 therebetween.

The inner member 11 comprises a core of laminated magnetic material 14 which is suitably slotted to receive a polyphase winding 15. Such a winding, which is shown a three phase winding for the purpose of illustration, has terminals as at 16, 17 and 18. Similarly, the outer member 12 comprises a core of laminated magnetic material 14a which is provided with a threephase winding 19 having terminals 20, 21, 22.

There is further provided for movement in the air gap 13, one or more shuttle bodies 23, as shown in Fig. 3. Such body may be of rectangular cross section and arcuate in its longitudinal extent to conform to the curvature of the air gap. The body 23 may be formed of plastic or other non-electrical conducting material and may be hollow to receive the bobbin. The opposite ends of the shuttle may be beveled in a known manner. Each of the bodies 23 has electrical conductors mounted on opposite sides thereof in the form of endless metal bands 24 which may take rectangular from. With the bodies 23 located in the air gap 13, the conductors 24 will be presented in opposed relation to the vertical faces of magnetic cores 14, 1451, as shown in Fig. 2.

It is understood that the shuttles 23 are adapted to move in a circular path within air gap 13 as an incident to the weaving operation involving sets of warp threads 25, 26, the shuttles being further adapted to move without contacting such warp threads as the same are manipulated in a manner known in the art.

In order to effect suitable movement of the bodies 23, there must be provided a force to overcome the force of gravity, a centripetal force to balance the centrifugal force and a propulsive force maintained at a uniform rate of speed. To this end, the windings 15, 19 are adapted to be energized with a system of polyphase currents having one fundamental angular frequency or pulsations with an amplitude periodically variable with another fundamental angular frequency or pulsations. Means for providing such a system of polyphase or sequential currents, is set forth in detail in application Ser. No. 209,953, filed February 8, 1951, now Patent 2,666,174, January 12, 1954, and application Ser. No. 200,959, filed December 15, 1950 now Patent 2,665,403, January 5, 1954.

Such means comprises essentially a monophase dynamo electric machine 27 connected to a polyphase dynamo electric machine 28. The machine 27 includes an armature 29 and a field winding 30 which is excited by direct current from a suitable source applied to terminals 31 thereof. The machine 28 includes a monophase field winding 32 which is energized by the output of machine 27, and an armature 33, which is shown as three phase for the purpose of illustration.

The output of the armature 33 is supplied to windings 15, 19 through a three phase autotransformer 34 having branches 35, 36, 37. The terminals 16, 17, 18 of winding 15 are respectively connected to taps 38, 39 and 40, respectively on branches 35, 36, 37 of the transformer. The terminals 20, 21, 22 of the winding 19 are respectively connected to taps 41, 42 and 43, respectively on branches 35, 36, 37 of the transformer.

Assuming that the machine 27 has a fundamental angular frequency or pulsations of W and the machine 28 has a fundamental angular frequency of pulsations of wz, then the system of sequential currents supplied to windings 15, 19 have instantaneous intensities in accordance with the formulae:

I =A sin w t sin 10 i I =A sin w t sin (10 25- I =A sin w t s1n (wt- As indicated in application Ser. No. 200,959, the value of m is greater than that of W2, A being a constant and t being the time interval for a full alternation cycle.

The energization of the windings 15, 19 will create a magnetic flux moving in the air gap with an angular speed equal to P where 2p is the number of poles on the windings. Such a flux is of variable intensity and alternates with a frequency W1. Accordingly, under the influence of the alternating flux, currents will be created in the conductors 24 and bodies 23 will be propelled in synchronism with the flux in the air gap 13. With such synchronous movement, a plurality of shuttles will maintain their spacing in relation to each other.

The conductors 24 on shuttles 23 have a longitudinal extent substantially equal to the polar pitch of the windings 15, 19. Accordingly, the total number of shuttles used may be determined by dividing the total number of poles of the winding by any integer which gives an integer quotient. Thus, in the case of a 12 pole winding, 12, 6, 4, 3, 2 or 1 shuttles may be used. Assuming that the shuttles must be equidistantly spaced in the air gap, then each shuttle will have an angular extent of 30. For a loom, where it is necessary to space the successive shuttles in order to permit the sets of warp threads to be crossed during the weaving operation, 1, 2, 3, 4 or 6 shuttles may be used.

The endless conductors 24 on the bodies 23 are proportioned to the magnetic poles of the system. Accordingly, if a body 23 is disposed in the air gap 13 so that the conductors are exactly symmetrically related to the alternating flux, no vertical forces will be developed. However, if the body 23 should move or tilt, electromagnetic forces will be developed in the conductors 24 tending to move the body back to its symmetrical position.

It has been found that the conductors 24 provide radial forces tending to repel the body 23 from the polar faces of the annular members 11, 12. Such forces are proportional to the square of the voltages applied to the respective windings on said members. By suitable regulation of the ratio of the voltages applied to the windings, through adjustment of the taps on autotransformer 34, a centripetal force may be developed which will balance the centrifugal forces created by the movement of the bodies 23 in the air gap 13. In addition, the spacing between the bodies 23 and the opposed faces of members 14, 14a may be adjusted.

In order to brake the movement of the shuttle bodies 23 and to bring the same to a halt, there is provided a switch 44 interposed in one of the leads from armature 33. Upon opening the switch 44, the polyphase system is converted to a monophase condition thereby fixing the alternating flux in space. Under such conditions, the bodies 23 will decelerate and come to a halt, while maintaining a floating relation to the pole faces of members 14, 14a.

It is understood that the polyphase winding on the inner member 11 may be omitted and the centripetal force necessary to overcome the centrifugal force, will be supplied by the flux created by winding 19 on member 12. Furthermore, the inner member 11 may be omitted altogether, but in the absence of a return path for the magnetic flux, a larger power input'to winding 19 will be required.

The underlying principles of the invention may be embodied in devices having a rectilinear air gap, as shown in Fig. 4. Here, a pair of spaced, parallel members 51, 52 provide an extended air gap '53 therebetween, in which shuttle bodies 231: are adapted'to move in a rectilinear path. The members 51, 52 comprise a magnetic core bearing polyphase windings which are adapted to be energized from a source of polyphase currents as described above.

In order to brake the bodies 23a at at predetermined point in the air gap, as at the opposite ends thereof, the members 51, 52 are provided with opposed sets of windings 54, 55; 56, 57. The windings 54, 55; 56, 57 are adapted to be energized by direct current applied to the terminals thereof, to create a permanent magnetic flux which is operative to brake the moving bodies 23:: as they come within the influence thereof. After braking, the bodies 23a, are reversed and placed in the air gap 53 so as to move in the opposite direction. The sets of warp threads, not shown, are located and manipulated in respect to the shuttles, in a manner known in the art.

It is understood that devices embodying the invention may be utilized wherever it is desired to provide synchro nous movement of one or more objects moving in a predetermined path. Furthermore, such path may have varied geometric forms, such as elliptical or the like, by subdividing the poylphase windings into sections and providing predetermined voltage inputs for the several sections in accordance with the radii of the respective sections.

As various possible embodiments might be made in the 7' above described invention, and as various changes might be made in the embodiments set forth, it is to be understood that all matter herein set forth or shown in the accompanying drawing is to be interpreted as illustrative and not in a limiting sense.

therebetween a path, at least one of said members including a magnetic core and a polyphase winding thereon, at

least one freely movable member disposed in said path, said movable member having mounted thereon electrical conductors providing a closed electrical circuit disposed in opposed relation to a face of said magnetic core, and means for energizing said winding with a system of sequential currents having substantially an intensity equal to the product of a constant, the sine of a first pulsation and the sine of a second pulsation different from said first mentioned pulsation, each current differing from a preceding current by an angular lag in one pulsation of said current proportional to the angular displacement of any pair of the successive polyphase windings whereby to provide a magnetic flux in said path interlinking the circuit on said movable member whereby said movable member will move in said path at a speed proportional to said first mentioned pulsation and in synchronous relation to said magnetic flux.

2. A device as in claim 1 and further including means for regulating the output voltage of said energizing means.

3. A device as in claim 1 wherein the other of said extended members comprises a magnetic core and a polyphase winding thereon, said energizing means being connected to said last mentioned winding.

4. A device as in claim 3 and further including means 7 for regulating the input voltage to the respective winding.

References Cited in the file of this patent UNITED STATES PATENTS 919,302 Armstrong Apr. 27, 1909 2,033,031 iosicek et al Mar. 3, 1936 2,112,264 Bowles et al Mar. 29, 1938 2,135,373 Wilson Nov. 1, 1938 2,487,148 Latieule et al. Nov. 8, 1949 2,630,839 Birtwell Mar. 10, 1953 FOREIGN PATENTS 303,119 Great Britain May 16, 1929 374,741 Great Britain June 16, 1932 483,816 Great Britain Apr. 25, 1938 

